The "How-to-do-it" Books
PRACTICAL MECHANICS FOR BOYS
THE "HOW-TO-DO-IT" BOOKS
PRACTICAL MECHANICS
FOR BOYS
In language which every boy can understand and so arranged that he may readily carry out any work from the instructions given.
WITH MANY ORIGINAL ILLUSTRATIONS
By J. S. ZERBE, M.E.
Author of
CARPENTRY FOR BOYS ELECTRICITY FOR BOYS
M. A. DONOHUE & COMPANY
CHICAGO :: NEW YORK
Copyright, 1914, by
THE NEW YORK BOOK COMPANY
Made in U. S. A.
CONTENTS
Introductory Page 1 I. On Tools Generally Page 7Varied Requirements. List of Tools. Swivel Vises. Parts of Lathe. Chisels. Grinding Apparatus. Large Machines. Chucks. Bench Tools. Selecting a Lathe. Combination Square. Micrometers. Protractors. Utilizing Bevel Protractors. Truing Grindstones. Sets of Tools. The Work Bench. The Proper Dimensions. How Arranged.
II. How to Grind and Sharpen Tools Page 26Importance of the Cutting Tool. The Grinder. Correct Use of Grinder. Lathe Bitts. Roughing Tools. The Clearance. The Cutting Angle. Drills. Wrong Grinding. Chisels. Cold Chisels. System in Work. Wrong Use of Tools.
III. Setting and Holding Tools Page 34Lathe Speed. The Hack-saw. Hack-saw Frame. The Blade. Files. Grindstones. Emery and Grinding Wheels. Carelessness in Holding Tools. Calipers. Care in Use of Calipers. Machine Bitts. The Proper Angle for Lathe Tools. Setting the Bitt. The Setting Angle. Bad Practice. Proper Lathe Speeds. Boring Tools on Lathe. The Rake of the Drill. Laps. Using the Lap. Surface Gages. Uses of the Surface Gage.
p. ii IV. On the First Use of the File Page 48The First Test. Filing an Irregular Block. Filing a Bar Straight. Filing Bar with Parallel Sides. Surfacing Off Disks. True Surfacing. Precision Tools. Test of the Mechanic. Test Suggestions. Use of the Dividers. Cutting a Key-way. Key-way Difficulties. Filing Metal Round. Kinds of Files. Cotter-file. Square. Pinion. Half-round. Round. Triangular. Equalizing. Cross. Slitting. Character of File Tooth. Double Cut. Float-cut. Rasp Cut. Holding the File. Injuring Files. Drawing Back the File.
V. How to Commence Work Page 61Familiarity with Tools. File Practice. Using the Dividers. Finding Centers. Hack-saw Practice. Cutting Metal True. Lathe Work. First Steps. Setting the Tool. Metals Used. The Four Important Things. Turning Up a Cylinder. Turning Grooves. Disks. Lathe Speeds.
VI. Illustrating Some of the Fundamental Devices Page 68Belt Lacing. Gears. Crown Wheel. Grooved Friction Gearing. A Valve which Closes by the Water Pressure. Cone Pulleys. Universal Joint. Trammel for Making Ellipses. Escapements. Simple Device to Prevent a Wheel or Shaft from Turning Back. Racks and Pinions. Mutilated Gears. Simple Shaft Coupling. Clutches. Ball and Socket Joints. Tripping Devices. Anchor Bolt. Lazy Tongs. Disk Shears. Wabble Saw. Crank Motion by a Slotted Yoke. Continuous Feed by Motion of a Lever. Crank Motion. Ratchet Head.p. iii Bench Clamp. Helico-volute Spring. Double helico-volute. Helical Spring. Single Volute Helix Spring. Flat Spiral, or Convolute. Eccentric Rod and Strap. Anti-dead Center for Lathe.
VII. Properties of Materials Page 79Elasticity. Traction. Torsion. Flexure. Tenacity. The Most Tenacious Metal. Ductility. Malleability. Hardness. Alloys. Resistance. Persistence. Conductivity. Equalization. Reciprocity. Molecular Forces. Attraction. Cohesion. Adhesion.
Lines in Drawing. Shading. Direction of Shade. Perspectives. The Most Pronounced Lines. Direction of Light. Scale Drawings. Degree, and What it Means. Memorizing Angles. Section Lining. Making Ellipses and Irregular Curves. Focal Points. Isometric and Perspective. The Protractor. Suggestions in Drawing. Holding the Pen. Inks. Tracing Cloth. Detail Paper. How to Proceed. Indicating Material by Section Lines.p. iv
IX. Treatment and Use of Metals Page 112Annealing. Toughness and Elasticity. The Process. Tempering. Tempering Contrasted with Annealing. Materials Used. Gradual Tempering. Fluxing. Uniting Metals. Alloying Method. Welding. Sweating. Welding Compounds. Oxidation. Soldering. Soft Solder. Hard Solder. Spelter. Soldering Acid. The Soldering Iron.
X. On Gearing, and How Ordered Page 121Spur and Pinion. Measuring a Gear. Pitch. Diametral Pitch. Circular Pitch. How to Order a Gear. Bevel and Miter Gears. Drawing Gears. Sprocket Wheels.
XI. Mechanical Power Page 128The Lever. Wrong Inferences from Use of Lever. The Lever Principle. Powers vs. Distance Traveled. Power vs. Loss of Time. Wrongly-Directed Energy. The Lever and the Pulley. Sources of Power. Water Power. Calculating Fuel Energy. The Pressure or Head. Fuels. Power from Winds. Speed of Wind and Pressure. Varying Degrees of Pressure. Power from Waves and Tides. A Profitable Field.
XII. On Measures Page 139Horse Power. Foot Pounds. Energy. How to Find Out the Power Developed. The Test. Calculations. The Foot Measure. Weight. The Gallon. The Metric System. Basis of Measurement. Metrical Table, Showing Measurements in Feet and Inches.p. v
XIII. Useful Information for the Workshop Page 148Finding the Circumference of a Circle. Diameter of a Circle. Area of a Circle. Area of a Triangle. Surface of a Ball. Solidity of a Sphere. Contents of a Cone. Capacity of a Pipe. Capacity of Tanks. To Toughen Aluminum. Amalgams. Prevent Boiler Scaling. Diamond Test. Making Glue Insoluble in Water. Taking Glaze Out of Grindstone. To Find Speeds of Pulleys. To Find the Diameters Required. To Prevent Belts from Slipping. Removing Boiler Scale. Gold Bronze. Cleaning Rusted Utensils. To Prevent Plaster of Paris from Setting Quickly. The Measurement of Liquids with Spoons.
XIV. Simplicity of Great Inventions and of Nature's Manifestation Page 152Invention Precedes Science. Simplicity in Inventions. The Telegraph. Telephone. Transmitter. Phonograph. Wireless Telegraphy. Printing Telegraph. Electric Motor. Explosions. Vibrations in Nature. Qualities of Sound. The Photographer's Plate. Quadruplex Telegraphy. Electric Harmony. Odors. Odophone. A Bouquet of Vibrations. Taste. Color.
XV. Workshop Recipes and Formulas Page 160Adhesives for Various Uses. Belt Glue. Cements. Transparent Cement. U. S. Government Gum. To Make Different Alloys. Bell-metal. Brass. Bronzes. Boiler Compounds. Celluloid. Clay Mixture for Forges. Modeling Clay. Fluids for Cleaning Clothes, Furniture, etc. Disinfectants. Deodorants. Emery for Lapping Purposes. Explosives. Fulminates. Files, and How top. vi Keep Clean. Renewing Files. Fire-proof Materials or Substances. Floor Dressings. Stains. Foot Powders. Frost Bites. Glass. To Frost. How to Distinguish. Iron and Steel. To Soften Castings. Lacquers. For Aluminum and Brass. Copper. Lubricants. Paper. Photography. Plasters. Plating, Coloring Metals. Polishes. Putty. Rust Preventives. Solders. Soldering Fluxes. Steel Tempering. Varnishes. Sealing Wax.
XVI. Handy Tables Page 178Table of Weights for Round and Square Steel. Table of Weight of Flat Steel Bars. Avoirdupois Weight. Troy Weight. Apothecaries' Weight. Linear Measure. Long Measure. Square Measure.
The Machinist's Opportunities. What is an Inventor? Idea Not Invention. What an Invention Must Have. Obligation of the Model Builder. Paying for Developing Devices. Time for Filing an Application. Selling an Unpatented Invention. Joint Inventors. Joint Owners Not Partners. Partnerships in Patents. Form of Protection Issued by the Government. Life of a Patent. Interference Proceedings. Concurrent Applications. Granting Interference. Steps in Interference. First Sketches. First Model. First Operative Machine.p. vii Preliminary Statements. Proving Invention. What Patents Are Issued For. Owner's Rights. Divided and Undivided Patents. Assignments. How Made. What an Invention Must Have. Basis for Granting Patent in the United States. Reasons for Granting Abroad. Original Grants of Patents. International Agreement. Application for Patents. Course of Procedure. Costs. Filing a Matter of Secrecy.
Glossary of Words Page 195 Index Page 213LIST OF ILLUSTRATIONS
p. ix
FIG. PAGE 1. Bench vise 8 2. Pipe grip for vise 9 3. Swivel vise 10 4. Speed lathe 11 5. Calipers 12 6. Engine lathe 13 7. Center gage 14 8. Pocket screw and wire gage 15 9. Handy bench vise 16 10. Combination square 17 11. Uses of the combination square 18 12. A quick adjusting micrometer 19 13. Universal bevel protractor 20 14. Uses of universal bevel protractor 21 15. Grindstone truing device 22 16. Set of tools and case 23 17. The work bench 24 18. Hook tool 28 19. Parting tool 28 20. Knife tool 28 21. Right-hand side toolp. x
34. Angles for tools 39 35. Set of the bitt 40 36. Correct angle 41 37. Wrong angle 41 38. Too low 42 39. Improper set 42 40. Internal set 43 41. Set for brass 43 42. Surface gage 44 43. Uses of surface gage 46 44. Rounded surface 49 45. Winding surface 49 46. Hexagon nut 51 47. Laying off hexagon nut 51 48. Cutting key-way 52 49. Key-seat rule 54 50. Filing metal round 54 51. Filing metal round 54 52. Making a round bearing 55 53. Making a round bearing 55 54. Cross section of filep. xi
72. Rack and pinion 73 73. Mutilated gears 73 74. Shaft coupling 73 75. Clutches 75 76. Ball and socket joints 75 77. Fastening ball 75 78. Tripping devices 75 79. Anchor bolt 75 80. Lazy tongs 75 81. Disc shears 75 82. Wabble saw 76 83. Continuous crank motion 76 84. Continues feed 76 85. Crank motion 76 86. Ratchet head 76 87. Bench clampp. xii
110. Lines on plain surfaces 101 111. Illustrating degrees 102 112. Section lining 103 113. Drawing an ellipse 104 114. Perspective at angles 106 115. Perspective of cube 107 116. Perspective of cube 107 117. Perspective of cube 107 118. Protractor 108 119. Using the protractorp. 1
PRACTICAL MECHANICS FOR BOYS
INTRODUCTORYToC
The American method of teaching the mechanical arts has some disadvantages, as compared with the apprentice system followed in England, and very largely on the continent.
It is too often the case that here a boy or a young man begins work in a machine shop, not for the avowed purpose of learning the trade, but simply as a helper, with no other object in view than to get his weekly wages.
Abroad, the plan is one which, for various reasons, could not be tolerated here. There he is bound for a certain term of years, and with the prime object of teaching him to become an artisan. More often than otherwise he pays for this privilege, and he knows it is incumbent on him "to make good" right from the start.
He labors under the disadvantage, however, that he has a certain tenure, and in that course he is not pushed forward from one step to the next on account of any merit of his own. His advancement is fixed by the time he has put in at eachp. 2 part of the work, and thus no note is taken of his individuality.
Here the boy rises step after step by virtue of his own qualifications, and we recognize that one boy has the capacity to learn faster than another. If he can learn in one year what it requires three in another to acquire, in order to do it as perfectly, it is an injury to the apt workman to be held back and deterred from making his way upwardly.
It may be urged that the apprentice system instills thoroughness. This may be true; but it also does another thing: It makes the man a mere machine. The true workman is a thinker. He is ever on the alert to find easier, quicker and more efficient means for doing certain work.
What is called "Efficiency" in labor methods, can never obtain in an apprenticeship system for this reason. In a certain operation, where twelve motions are required to do a certain thing, and a minute to perform the twelve operations, a simplified way, necessitating only eight motions, means a difference in saving one-third of the time. The nineteen hundred fewer particular movements in a day's work, being a less strain on the operator, both physically and mentally, to say nothing whatever of the advantages which the proprietor of the shop would gain.p. 3
I make this a leading text in the presentation of this book; namely, that individual merit and stimulus is something of such extreme importance that it should be made the keynote for every boy who tries to become a mechanic.
The machinist easily occupies a leading place in the multitude of trades and occupations. There is hardly an article of use but comes to the market through his hands. His labor is most diverse, and in his employment doing machine work he is called upon to do things which vary widely in their character.
These require special knowledge, particular tools, and more frequently than otherwise, a high order of inventive ability to enable him to accomplish the task.
The boy should be taught, at the outset, that certain things must be learned thoroughly, and that habits in a machine shop can be bad as well as good. When he once becomes accustomed to putting a tool back in its rightful place the moment he is through with it, he has taken a long step toward efficiency.
When he grasps a tool and presents it to the work without turning it over several times, or has acquired the knack of picking up the right tool at the proper place, he is making strides inp. 4 the direction of becoming a rapid and skilled workman.
These, and many other things of like import, will require our attention throughout the various chapters.
It is not the intention of the book to make every boy who reads and studies it, a
It also analyzes the manner in which the job is laid out; how to set the tools to get the most effective work; and explains what is meant by making a finished piece of workmanship. These things, properly acquired, each must determine in his own mind whether he is adapted to follow up the work.
Over and above all, we shall try to give the boy some stimulus for his work. Unless he takes an interest in what he is doing, he willp. 5 never become an artisan in the true sense of the word.
Go through the book, and see whether, here and there, you do not get some glimpses of what it means to take a pleasure in doing each particular thing, and you will find in every instance that it is a satisfaction because you have learned to perform it with ease.
I do not know of anything which has done as much to advance the arts and manufactures, during the last century, as the universal desire to improve the form, shape and structure of tools; and the effort to invent new ones. This finds its reflection everywhere in the production of new and improved products.
In this particular I have been led to formulate a homely sentence which expresses the idea: Invention consists in doing an old thing a new way; or a new thing any way.
The Author.